Method of determining spatial distribution of ionospheric inhomogeneities

FIELD: physics.

SUBSTANCE: invention relates to radiophysical methods of investigating the ionosphere and is intended for determining spatial distribution of ionospheric inhomogeneities by a radar method using a linear FM ionosonde-radio direction-finder. The method includes probing the ionosphere with a broadband chirp signal; receiving the emitted chirp signal synchronously with transmission thereof; measuring the distance-frequency characteristics (DFC) and angular frequency characteristics (AFC) of all received signals (forward and scattered by ionospheric inhomogeneities); based on an ionospheric model and the measured DFC and AFC, calculating characteristics of the forward signal propagating on an arc of a large circle between the transmitter and the receiver; correcting the ionospheric model until the measured and calculated characteristics of the forward signal match; for the calculated ionospheric model and measurement data of the DFC and AFC of the scattered signal, calculating characteristics of the scattered signal until the measured and calculated data match and determining spatial distribution of ionospheric inhomogeneities based thereon.

EFFECT: high accuracy of determining spatial distribution of small-scale inhomogeneities of electron concentration, provided by increasing the probing frequency to a value higher than the critical frequency of the ionospheric F-layer, for detecting signals scattered by the ionospheric inhomogeneities with high frequency-time resolution, and positioning the inhomogeneities.

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The invention relates to radiophysical research methods ionospheric plasma and is intended to determine the spatial distribution of ionospheric irregularities radar method using the chirp ionosonde - finder. Study of ionospheric irregularities is important for understanding the physical processes in the upper atmosphere, and to solve practical problems of radio communication, radio navigation, radio and radar systems, because of heterogeneity lead to fading and variations of the angles of arrival of the signal, which reduces the efficiency of electronic systems for various purposes. For the study of ionospheric irregularities and determine their parameters are different experimental methods and technique of measurement. The most highly developed method of vertical sounding of the ionosphere (Singleton D.G. The morphology of spread F occurrence over half a sunspot cycle. J. Geophys. Res. 1968, v.73, pp.295-308; RF patent №2403592 for the invention "Method of determining the value of intensity inhomogeneities in the ionosphere in the vertical sounding data"). In addition, to study inhomogeneities applied methods such as a method of scintillation using radio signals of the satellite (R.K. Crane Ionospheric scintillation. Proc. IEEE. 1977, v.65, p.180), direct probe measurements from aboard rockets and satellites (P.L. Dyson, J.P. McClure, W.B. Hanson I situ measurements of the spectral characteristics of ionospheric irregularities. J. Geophys. Res. 1974, v.79, p.1497; R.F. Pfaff, M.C. Kelley, B.G. Fejer et al. Electric field and plasma density measurements in the auroral electrojet. J. Geophys. Res. 1984, v.89, pp.236-244; Kelley M.C., Arce T.L., J. Salowey, et al. Density depletions at the 10-m scale induced by the Arecibo heater J. Geophys. Res. 1995. v. 100, no. A9, p.17367-17376), transionospheric sensing using radio signals of navigation satellites GLONASS (Russian Federation patent No. 2421753 for the invention "method for determining the parameters of the ionosphere and the device for its implementation"), are also used radar incoherent and coherent scattering of radio waves (Hagfors So The EISCAT facility. High-latitude space plasma physics. New York; London: Plenum Press, 1983, p.1-9; RF patent №2251713 "Method of determining the electron concentration in a given region of the ionosphere and the device for its implementation"; J.M. Ruohoniemi, J.P. Villain et al. Coherent HF radar backscatter from small-scale irregularities in the dusk sector of the subauroral ionosphere. J. Geophys. Res. 1988, v.93, pp.12871-12882). Each of these methods has its advantages and disadvantages. So measuring from the Board of rockets and satellites though and have high spatial resolution, but are episodic in nature. Low resolution vertical sounding stations does not allow for detailed localization of the scattering inhomogeneities. The same drawback is different and the method of scintillation of radio signals of the satellite. The incoherent scatter radar has high spatial resolution, but is a very expensive tool. the agifts coherent scattering, networked SuperDARN radars (Greenwald R.A., Baker, C.V., J.R. Dudeney et al. Darn/Superdarn: A global view of the dynamics of high-latitude convection // Space Sci. Rev. 1995, v.71, p.761)are intended for research only high-latitude irregularities and have restrictions on the positioning of ionospheric irregularities. The fact that in conditions of strong geomagnetic disturbances of auroral region with inhomogeneities moves in a southerly direction (lower latitude)and heterogeneity are out of sight of the radar under the terms resursnogo scattering of radio waves. In addition, the radars of the SuperDARN network work only on the number of fixed frequencies in a limited frequency range 8-20 MHz, which significantly reduces the possibility of such radars for monitoring ionospheric irregularities.

As the prototype was taken way to determine the altitude distribution of the intensity values of inhomogeneities in the ionosphere in the vertical sounding data (patent RF №2403592 "Method of determining the value of intensity inhomogeneities in the ionosphere in the vertical sounding data"), namely, that process the data of vertical sounding of the ionosphere and on each frequency sensing define the effective height of the reflection, sort the data on the frequency of each frequency sensing are associated with the current height of the expression, from which the reflected wave, sort the data on the height of each of the heights of reflection are associated with all those frequencies that were reflected from this height, determine the average value of the critical frequency of the reflection corresponding to each of the heights of reflection, comparing the average values of the frequencies reflect on the neighbouring heights of reflection one by one, starting with the first, when the difference between the two average values of the frequencies reflect on the neighbouring heights will be less than half pitch adjustment, determine the average value of the critical frequency, determine the current height of the reflection corresponding to the average value of the critical frequency, calculate the RMS value deviation of the critical frequency, determine the value of intensity inhomogeneities in the ionosphere.

Thus, the entire range of operating heights of reflection is divided into cells with a step of ∆ H_d=2 miles, then within each current interval is the average frequency of the reflection and the standard deviation of the frequency of reflection, and then determine the amount of intensity inhomogeneities in the ionosphere by dividing the doubled value standard deviation frequency reflections on the average frequency of reflection.

Beings who authorized the disadvantage of this method of determining the altitude distribution of the intensity values of inhomogeneities in the ionosphere, is the low altitude resolution, which can lead to distortion of the measured characteristics. The fact that in the presence of the extended height of the layer with inhomogeneities in the radio on the way of distribution to the point of reflection can experience the scattering forward on heterogeneities below the height of the reflection and the accumulation effect of the influence of inhomogeneities on the recorded signal of vertical sounding. Thus, the closer the studied interval of the effective height to the maximum height of the ionospheric layer, the greater the effect of the underlying heterogeneity on the measured characteristics of the reflected signal. Therefore, to obtain reliable information about the intensity of ionospheric irregularities, it is necessary to determine their spatial localization. Thus, the proposed method of estimation of intensity nonuniformities will not match the real altitudinal distribution of ionospheric irregularities.

The challenge which seeks the invention is to improve the accuracy of determining the spatial distribution of small-scale inhomogeneities of the electron concentration.

The solution of the stated technical problem is provided by the technical result consists in the possibility of providing povysheniya sensing to the value exceeding the critical frequency of the ionospheric F-layer, which allows high-frequency temporal resolution to detect the signals scattered ionospheric inhomogeneities, and be sure to separate them from the signals of the image channel. While vertical sounding at frequencies below the critical frequency of the ionosphere occurs the problem of separating the contribution of the specular signal and the signal scattered forward at depth height ionospheric inhomogeneities.

To achieve the specified result, in the method of determining the spatial distribution of ionospheric electron concentration irregularities, including the sounding of the ionosphere broadband linear frequency-modulated signal (chirp signal) from the transmitter, the reception of radiated broadband chirp signal is performed by the receiver synchronously with the transmission of the chirp signal, then measure the distance frequency (DCH) and angular frequency (UCH) characteristics of all registered (received) signals, then based ionospheric model and measured DCH and UCH conducting calculations of the characteristics of the direct signal propagating along the arc of a great circle between the transmitter and the receiver, correct ionospheric model to match the measured and settlement characteristics, and then adjusted for ionospherically and measurement data DCH and UCH scattered signal conducting calculations of the characteristics of the scattered signal to match the measured and calculated data, and for the whole array of measured data according to the parameters of the received scattered signal (frequency - delay - azimuth - elevation) determine the spatial distribution of ionospheric irregularities responsible for scattering: the height h and the geographical coordinates (latitude φ and longitude λ) podonominae field scattering.

As broadband receiver, the chirp signal using the chirp ionosonde-finder mode inclined wideband sensing for measurement of key characteristics of the radio signals scattered ionospheric inhomogeneities: remotely-frequency (DCH), the amplitude and angular frequency (UCH) characteristics, modeling of radio wave propagation and positioning of the heterogeneity based matching of measured and calculated characteristics of radio signals.

The basis of the way put the radar method using oblique broadband chirp sensing bistatic configuration placement of the transmitter and receiver relative to the study area of the ionosphere. The transmitter and receiver are located at a distance of ~500-2000 km South from this area and at a distance of ~500-1500 km from each other. This location of the probe means is caused by the peculiarities of wave scattering on small-scale magnetic-oriented IO is overnig inhomogeneities [Yakovlev, I., Yakubov V.P., Uryadov V.P., Pavelyev A.G. Propagation of radio waves. Textbook for high schools. M: LENAND. 2009, 496 S.].

Use in the receiving item, the chirp ionosonde-finder allows you to divide latency (slant range) and angle of arrival all fashion spread and measurements remotely-frequency (DCH), the amplitude and angular frequency (UCH) characteristics of both direct and scattered signals.

The procedure for determining the spatial distribution of ionospheric irregularities responsible for the scattered signals is as follows:

1. Under the program, tied to the timeline, the chirp transmitter and the parameters of the emitted chirp signal (start frequency, end frequency, rate of frequency change, the beginning of the radiation period sensing) run ionospheric probe finder.

2. Carry out a reception signal, the chirp transmitter and measure DCH and OUCH on the track sounding.

3. For each session of measurements DCH and UCH correct model profile of the electron concentration thus, to achieve the best agreement of the calculated monogramma direct signal propagating along the arc of a great circle between the transmitter and the receiver, with the experimental data (remotely-frequency response (DCH) and the dependence of the angle m is a hundred and azimuth coming to the point of observation of the signal from the frequency (UCH)) to the direct signal.

4. For the thus obtained an adapted model of the ionosphere perform the simulation of the scattered signals. Primary data are the results of measurements of the delays and angles of arrival (azimuth and elevation) of the scattered signals. The collection point with the measured values of the azimuth and elevation calculated beam trajectory in the direction of the field with the ionospheric inhomogeneities responsible for the scattering. For each radial trajectories passing through the ionosphere with inhomogeneities, calculate the beam coming to the point of location of the transmitter. Then determine the total delay on the track transmitter - area dispersion - receiver. As soon as this delay is measured experimentally, this area scattering positioned believe. This procedure is performed for the whole array of measured data according to the parameters of the received scattered signal (frequency - delay - azimuth - elevation).

5. Next, based on the matching of measured and calculated characteristics of the scattered signals determines the spatial location of ionospheric irregularities, i.e. find the height h and the geographical coordinates (φ, λ) podonominae field scattering.

The claimed method can be implemented using the device, the block diagram of which is shown in Fi is .1. The device consists of two separate units 1 and 2. The transmitting device 1 and the receiving device 2 outlined by dash-and-dot lines in figure 1.

The transmitter device 1 includes: a GPS antenna 3 connected to the input of the GPS receiver 4, the block timing 5, the antenna of the transmitter chirp signals 6 that is connected to the output of the transmitter chirp signals 7, the chirp generator of the transmitter 8, the computer 9 to control the operation of the transmitting device 1. Thus the output of the GPS receiver 4 is connected to the input of the block timing 5, the transmitter input chirp signal 7 is connected to the output of the chirp generator 8, an input connected to the output of the computer 9, the input of the computer 9 is connected to the output of the block timing 5.

The receiving device 2, which represents the chirp ionosonde-finder includes a GPS antenna 10, is connected to the GPS receiver 11, the block timing 12, the first input of which is connected to the output of the GPS receiver 11, TV-antenna element grating 13, the coupler 14 to the input of which is connected one of the elements of the antenna array 13 (reference antenna), the antenna switch 15, to the first input of which is connected to the first output of the splitter 14, to the other N- inputs of switch 15 is connected to the N-1 elements of the antenna array 13, the chirp generator of the receiver 16, the first the inlet of which is connected to the first output block time sin is anizatio 12, the first receiver device (RPU) 17, the first input of which is connected to the second output of the coupler 14, the second input RPU 17 connected to the first output of the chirp generator of the receiver 16, the second receiver device (RPU) 18, the first input of which is connected to the output of the antenna switch 15, the second input RPU 18 is connected to the second output of the chirp generator of the receiver 16, a two-channel analog-to-digital Converter (ADC) 19, the first input of which is connected to the output BU 17, the second ADC input 19 connected to the output BU 18, the third ADC input 19 is connected to the second output unit timing 12, the output of the dual-channel ADC 19 is connected to the input of a multi-threaded computer 20 (circled in figure 1 by the dashed line). While the input multi-threaded computer 20 has a unit 21, where the estimation of the spectral power density (MTA) of the signal and noise detection rays, determination of their number n, the amplitude of each beam α_jdelays of each beam τ_jcoefficient of turbidity of the ionosphere β²the measurement of two-dimensional angular coordinates of each j-th beam by Fourier synthesis of antenna directional diagram. The first input unit 21 is connected to the output of the dual-channel ADC 19. Output multithreaded computer 20 has a user interface 22, the first output of which is coincident with the first output megapath knogo transmitter 20, connected to the second input of the chirp generator 16, the second output of the user interface 22, coinciding with the second output multithreaded computer 20 connected to the N+1 input of the antenna switch 15, the third output of the user interface 22, coinciding with the third output multithreaded computer 20 connected to the second input of the block timing 12, the fourth output of the user interface 22 is connected to a second input of the processing unit of the measured characteristics of the direct and scattered signals 21, the output of which is connected to the input of block 23 modeling and determining the spatial distribution of small-scale ionospheric irregularities, display output information.

The device consists of the following basic steps.

1. Under the program, tied to the timeline, the chirp transmitter and the parameters of the emitted chirp signal (start frequency, end frequency, rate of frequency change, the beginning of the radiation, the sensing period), with the user interface 22 run ionospheric probe finder, including block start timing 12 and respectively connected to the block timing 12 ADC 19, the antenna switch 15, the chirp generator 16 and the processing unit of the measured characteristics of the direct and Russian the th signal 21.

2. Carry out a reception signal, the chirp transmitter using the antenna array 13 of the receiver 2. From the output of the reference antenna (one of the elements of the antenna array 13) through the splitter 14, the signal at the first input RPU 17 (reference channel). To support the antenna RPU 17 is connected continuously to provide continuous sampling of the signal in the reference channel. To the second input RPU 17 receives the signal from the first output of the chirp generator 16. The differential signal generated by the multiplication of the signal received at CU 17 from the splitter 14, the signal received at RPU 1 17 from the chirp generator 16, is fed from the output of the 2nd intermediate frequency (if) RPU 17 at the first input of the ADC 19.

3. Using the antenna switch 15 to RPU 18 alternately connect all the antenna elements, and the chirp signal transmitter, adopted by the antenna 13, is fed to the first input RPU 18 (specific channel), to the second input RPU 18 receives the signal from the second output of the chirp generator 16. The differential signal generated by the multiplication of the signal received at CU 18 from the antenna array 13, the chirp signal generator 16, is fed from the output of the 2nd inverter RPU 18 to the second input of the ADC 19.

4. When the switching of the antenna switch 15 both receiving device RPU 17 and CU 18 are connected to the reference antenna (one of the elements of the antenna array 13), what about the sampling signal with the reference antenna define a complex coefficient raznesennost (phase difference and amplitude ratio), describing the complex coefficients of the transmission support (formed by the splitter 14 and RPU 17) and the subject of the channels formed by the antenna switch 15 and RPU 18). In the future, this coefficient is used for the correction of complex relative amplitudes of the signals obtained from samples from other antenna elements. The result is a measure of the relative (with respect to a reference antenna) complex amplitudes of the signals from all antenna elements invariant under complex coefficients of the transmission channel two RPU.

5. Then the antenna switch switches the subject RPU 18 on the new antenna element and so on, the Switching is carried out until, until the end of the reception signal from the chirp transmitter. In each moment of time dual RPU consisting of CU 17 and CU 18 is connected to the reference antenna (one of the elements of the antenna array 13) and another element from an N-element antenna array 13. With each pair of antenna elements is a sample of a signal of length M for digitization by the ADC 19 with frequency f_dand sampling increment$$\Delta t=\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$f_d$}\right.$$. The value of M is chosen so that, provided the temporal resolution of the partial beams is rasprostraneniya group delay. So, when speed adjustment frequency 100 kHz/s and band analysis, the chirp signal is 20 kHz time sampling is 200 MS. For the time resolution of the partial beams according to the group delay of ~50 μs, the value of M is assumed to be 4096. The average frequency of the received signal is equal to$$f_{nl}=f_{\min }+{\mu }_0\Delta t\left(MNl+M\frac{2n+1}{2}\right)$$where h=1, 2, ...N - number of respondents antenna element, l=1, 2, ..., L is the number of discrete frequencies, which will be assessed angles of arrival,$$L=\frac{f_{\max }-f_{\min }}{{\mu }_0\Delta tMN}$$λ is the number of discrete frequencies, µ₀- speed adjustment frequency f_minand f_max- minimum and maximum frequency range sensing. The angles of arrival are assessed based on a uniform frequency grid, and the values of the frequencies are determined by the ratio of. After a full crawl of all N elements of the antenna array 13 on the intermediate frequency receivers RPU 17 and CU 18 with an average of discrete carrier frequency f_lfor each pair of channels ADC 19 receive coherent sampling digital differential signal for the reference channel {x_lm} and subject channel {x_nm}, where n=1, 2,..., N, m=1, 2, ..., M.

6. Processing the digitized difference signal is performed using a multi-threaded computer 20. For this ADC output 19 digitized differential signal from two RPU is fed to the input unit 21 included in the multi-threaded computing device 20, where the estimation of the spectral power density (MTA) signal and noise multi-window method (MTM-method)are detected rays, determination of their number n, the complex amplitudes α_j, delays τ_j, turbidity coefficient β². For each pair of samples of the difference signal for the reference channel {x_lk} and subject channel {x_nk} calculated spectra of the signals {s_lk}=FFT(x_lmand {s_nk}=FFT (x_nm), where k=1, ...M/2, FFT operator of the discrete Fourier transform performed on the basis of the algorithm of the fast Fourier transform (FFT). For each sample of a signal of length M with the n-th and the Tenno element using the FFT algorithm calculates the complex spectrum of the signal and calculates the power spectral density of the signal MTM method. The complex signal spectrum is used to calculate the relative transmission coefficient in the band RPU when connecting RPU 17 and CU 18 to the reference antenna (one of the elements of the antenna array 13). Power spectral density of the noise is determined by the histogram method (Vertogradov GG, Uryadov V.P., Vertogradova Mrs x, a Hardware-software complex to determine the optimal operating frequency of the coherent radio link according to the oblique sounding of the ionosphere. 1. Methods and algorithms of data processing. // Proceedings of XIII international scientific-technical conference "Radar Navigation Link. 17-19 April 2007. , Voronezh: SEQUOIA, Vol.2, s-1214). On the basis of statistical criteria (F-statistic) in the MTM method is the selection of discrete rays distribution (definition of their number (J), delays rays τ_j(f), the complex amplitudes a_j(f)determining the power dissipated components and, as a consequence, determination of turbidity coefficient β². Here, for each selected j-th beam is amplitude-phase distribution (PRA) field on the aperture of the antenna arraywhere j=1, 2...J - number of the beam, n=1, 2, ..., N is the number of antenna element, l=1, 2, ..., L is the number of discrete frequencies, which will be assessed angles of arrival. Pras each beam is subsequently used for the Fourier synthesis of the chart on which ravennati and evaluation of two-dimensional angular coordinates of the beam α _j- azimuth of arrival in the Earth plane and Δ_j- the elevation angle in the vertical plane.

In the same block is clean ionogram, the selection of the frequency of branches and the formation of dependencya_j(f), τ_j(f)signal/noise (s/n)_j(f),$${\beta }_j^2\left(f\right)$$the determination of the lowest observed frequencies (NNC), the maximum observed frequency (MNC), spacing of multipath propagation, interval temporal dispersion Δτ, the standard deviation ratio (s/n) σ_s/W, error probability, the reliability of the connection.

Here is the measurement of two-dimensional angular coordinates of each j-th beam by Fourier synthesis of antenna directional diagram of the antenna array and the final cleanup ionogram on the basis of the criterion of validity of estimation of angles of arrival.

Here is the formation of a remotely-frequency, amplitude-frequency and two-dimensional angular-frequency characteristics, and MN, NC, level of spectral noise, turbidity coefficient, the probability of error, the reliability of the connection.

7. From the output of block 21, the measurement results are sent to the input block 23 modeling of the characteristics of ionospheric radio wave propagation, where taking into account correction the ionospheric model for modeling of the direct and scattered signals, and based on the matching of measured and calculated characteristics of the scattered signal is the spatial distribution of ionospheric irregularities responsible for the scattered signals. The results of the operation of the device that implements the claimed method, are printed in the form of a table with 3-dimensional coordinates of the location of ionospheric irregularities responsible for scattering: the height h and the geographical coordinates podonominae region scattering (latitude φ and longitude λ).

The feasibility of this method was confirmed in a series of experiments conducted by the authors on the track of the inclined chirp sensing Cyprus-Rostov-on-don.

As a transmitter, the chirp signal was used broadband chirp transmitter, located in Cyprus, who worked in the frequency range 8-30 MHz, the speed adjustment frequency is 100 kHz/sec

As a receiver, the chirp signal was used, the chirp of ion-probe-finder located in the neighborhood, Rostov-on-don, created on the basis of two coherent radio receivers R-A and antenna array in the form of 16 vertical vibrators with a height of 9 m, site measuring 100×100 m².

Figure 2 shows an example of a device that implements the inventive method, on the track Cyprus-Rostov-on-don, when for a long time is time 17:30 UT on 04 January 2012 to 02:00 UT on January 05, 2012 were recorded scattered signals. Figure 2 shows DCH (a), frequency response (b) and UCH (the elevation angle Δ (deg.), Mr. azimuth α (deg.)) all recorded signals on the track, the chirp sensing Cyprus-Rostov-on-don. 01:04 UT, 05.01.2012,

Direct and scattered signals are marked in figure 2 markers substation and PC1-PC3, respectively. To validate the proposed method, we carried out analysis of the results of measurements of diffusely scattered signal PC3, which was observed at frequencies above the maximum observed frequency (MNC) direct signal, equal to 13.5 MHz. According to the results of measurements of the scattered signal RSZ, on average, he had the following parameters: delay range ~ 7-11 MS, frequency range ~ 14-19 MHz, spacing, vertical angles of arrival ~20-45°, the interval of the azimuthal angles of arrival ~330-50°, the signal amplitudePC3was 50-60 dB less than the amplitude of the direct signal. As can be seen from figure 2, along with the signal PC1, monogramma were recorded signals back-inclined sounding (BIS), the marked PC1 and PC2, which are characterized by growth delays with increasing frequency (Chernov Y.A. Back and oblique sounding of the ionosphere. M: Communications. 1971, 204 S.).

For positioning areas, responsible for the appearance of scattered signals, we performed a simulation of the characteristics of direct and scattered signalov calculations use the international reference model of the ionosphere IRJ (Bilitza D., International Reference Ionosphere 2000, Radio Sci. 2001, v.36, pp.261-275). On the basis of comparison of the calculated and experimental characteristics of the scattered signals according to the measurement results of the delay (range), vertical and azimuthal angles of arrival of the scattered signals PC1-RS held positioning areas with inhomogeneities responsible for the scattered signals. The results plotted on a physical map and shown in figure 3, which shows the location of the areas responsible for the scattered signals PC1-RS, for sensing session 01:04 UT, 05.01.2012,

On the basis of the measurement results and modeling delay (range), azimuthal and vertical angles of arrival of the scattered signal RHS found that this signal is caused by the scattering of radio waves from inhomogeneities of the electron concentration located in the extended region mid-latitude ionosphere in the range of latitudes ~50-55°N and longitudes ~35-48°E at altitudes of ~250-450 km Detailed data on the determination of the spatial location of ionospheric irregularities on the results of operation of the device for the analyzed session of measurements of scattered signals RS presented in table 1 in figure 4, where:

f - sonde frequency in MHz, t - signal delay in MS, the azimuth - the azimuth angle of arrival of a signal, measured clockwise from the North direction the Oia for receiving item in degrees, the elevation angle is the angle of arrival of the signal in the vertical plane, measured from the horizontal in degrees, h - the height of the scattering of ionospheric irregularities in km, f is the latitude of the projection on the Earth's surface area with ionospheric inhomogeneities in degrees, λ - longitude projection on the Earth's surface area with ionospheric inhomogeneities in degrees.

The presented data confirm the feasibility of the proposed method of determining the location of ionospheric irregularities.

As for the anomalous signals PC1 and RS, the results of measurements and simulations established that the mechanism of propagation of PC1 is connected with the scattering of radio waves from the Iranian plateau, and signal RS - scattering from the Central Russian and Volga heights.

The method of determining the spatial distribution of ionospheric irregularities, including the sounding of the ionosphere by the signal transmitter, receiving a sounding signal via the receiver, wherein the probing signal is a wideband linear frequency modulated signal (chirp signal), the reception of radiated broadband chirp signal is carried out synchronously with the transmission, measured remotely-frequency (DCH) and angular frequency (UCH) characteristics of the received signals, and then on the basis of ionospheric m is Delhi and measured DCH and UCH conducting calculations of the characteristics of the direct signal, propagating along the arc of a great circle between the transmitter and the receiver, correct ionospheric model to match the measured and calculated characteristics of the direct signal, and then adjusted for the ionospheric model and measurement data DCH and UCH scattered signal conducting calculations of the characteristics of the scattered signal to match the measured and calculated data and for the whole array of measured data according to the parameters of the received scattered signal (frequency - delay - azimuth - elevation) determine the spatial distribution of ionospheric irregularities responsible for scattering: the height h and the geographical coordinates (latitude φ and longitude λ) podonominae field scattering.